Error with function-lookup and static variable

On Fri, Aug 9, 2024 at 5:51 PM Amanda Galtman <galtmana at proton.me> wrote: > Hi, all. > > I'm seeing an error in BaseX when I use function-lookup in both a global > variable and a function, where the function relies on the variable. I > reduced the situation to the following small query: > > xquery version "3.1"; > declare variable $local:lookup := function-lookup(QName("nonexistent", > "nonexistent"), 1); > declare function local:myfcn() { > let $f := ($local:lookup, function-lookup(QName(' > http://www.w3.org/2005/xpath-functions','string'), 1))[1] > return $f('a') > }; > local:myfcn() > > When I run it with BaseX 11.1, I get > [XQDY0054] Static variable depends on itself: $local:lookup > > When I run it with Saxon-HE 12, I don't get this error. > > Is there anything I can do in my code to avoid this error? > > Thanks, > Amanda >

On Fri, Aug 9, 2024 at 5:51 PM Amanda Galtman <galtmana at proton.me> wrote: > Hi, all. > > I'm seeing an error in BaseX when I use function-lookup in both a global > variable and a function, where the function relies on the variable. I > reduced the situation to the following small query: > > xquery version "3.1"; > declare variable $local:lookup := function-lookup(QName("nonexistent", > "nonexistent"), 1); > declare function local:myfcn() { > let $f := ($local:lookup, function-lookup(QName(' > http://www.w3.org/2005/xpath-functions','string'), 1))[1] > return $f('a') > }; > local:myfcn() > > When I run it with BaseX 11.1, I get > [XQDY0054] Static variable depends on itself: $local:lookup > > When I run it with Saxon-HE 12, I don't get this error. > > Is there anything I can do in my code to avoid this error? > > Thanks, > Amanda >

On Monday, August 12th, 2024 at 4:43 AM, Christian Grün <christian.gruen at gmail.com> wrote: > Hi Amanda, > > It is high time to tackle an existing GitHub issue that most likely relates to the same bug [1]. > > Thanks for your observation, > Christian > > [1] https://github.com/BaseXdb/basex/issues/1095 > > On Fri, Aug 9, 2024 at 5:51 PM Amanda Galtman <galtmana at proton.me> wrote: > >> Hi, all. >> >> I'm seeing an error in BaseX when I use function-lookup in both a global variable and a function, where the function relies on the variable. I reduced the situation to the following small query: >> >> xquery version "3.1"; >> declare variable $local:lookup := function-lookup(QName("nonexistent", "nonexistent"), 1); >> declare function local:myfcn() { >> let $f := ($local:lookup, function-lookup(QName('http://www.w3.org/2005/xpath-functions','string'), 1))[1] >> return $f('a') >> }; >> local:myfcn() >> >> When I run it with BaseX 11.1, I get >> [XQDY0054] Static variable depends on itself: $local:lookup >> >> When I run it with Saxon-HE 12, I don't get this error. >> >> Is there anything I can do in my code to avoid this error? >> >> Thanks, >> Amanda

On Monday, August 12th, 2024 at 5:16 AM, Christian Grün <christian.gruen at gmail.com> wrote: > I managed to fix a part of the dependency problem. Your query should now be executable with the latest snapshot [1]. > – Christian > > [1] https://files.basex.org/releases/latest/ > > On Fri, Aug 9, 2024 at 5:51 PM Amanda Galtman <galtmana at proton.me> wrote: > >> Hi, all. >> >> I'm seeing an error in BaseX when I use function-lookup in both a global variable and a function, where the function relies on the variable. I reduced the situation to the following small query: >> >> xquery version "3.1"; >> declare variable $local:lookup := function-lookup(QName("nonexistent", "nonexistent"), 1); >> declare function local:myfcn() { >> let $f := ($local:lookup, function-lookup(QName('http://www.w3.org/2005/xpath-functions','string'), 1))[1] >> return $f('a') >> }; >> local:myfcn() >> >> When I run it with BaseX 11.1, I get >> [XQDY0054] Static variable depends on itself: $local:lookup >> >> When I run it with Saxon-HE 12, I don't get this error. >> >> Is there anything I can do in my code to avoid this error? >> >> Thanks, >> Amanda

On Wed, Aug 14, 2024 at 1:02 PM Amanda Galtman <galtmana at proton.me> wrote: > Christian, thanks very much. > > I returned to my actual code, and it works with the latest snapshot dated > today. > > By the way, I also retried the variations I had created when trying to > explore workarounds, and one of them still doesn't work with the latest > snapshot. It's not blocking me, but in case it is helpful, I reduced it to > another small query that reproduces the error with today's snapshot. I know > you said you fixed part of the problem, so you might not be surprised that > the following code still triggers the error. > > xquery version "3.1"; > > declare variable $variant := > if (exists(function-lookup(QName('nonexistent','nonexistent'), 0))) > then > ( (: not relevant :) ) > else > function-lookup(QName('http://www.w3.org/2005/xpath-functions','string'), > 1); > > declare variable $variant-fcns := $variant; > > declare function local:fcn() { > $variant-fcns('abc') > }; > > local:fcn() > > > The levels of indirection (variable, variable, function, function call) > seem to be relevant for the problem. If I make the code more direct, it > works. > > Regards, > Amanda > > On Monday, August 12th, 2024 at 5:16 AM, Christian Grün < > christian.gruen at gmail.com> wrote: > > I managed to fix a part of the dependency problem. Your query should now > be executable with the latest snapshot [1]. > – Christian > > [1] https://files.basex.org/releases/latest/ > > > > On Fri, Aug 9, 2024 at 5:51 PM Amanda Galtman <galtmana at proton.me> wrote: > >> Hi, all. >> >> I'm seeing an error in BaseX when I use function-lookup in both a global >> variable and a function, where the function relies on the variable. I >> reduced the situation to the following small query: >> >> xquery version "3.1"; >> declare variable $local:lookup := function-lookup(QName("nonexistent", >> "nonexistent"), 1); >> declare function local:myfcn() { >> let $f := ($local:lookup, function-lookup(QName(' >> http://www.w3.org/2005/xpath-functions','string'), 1))[1] >> return $f('a') >> }; >> local:myfcn() >> >> When I run it with BaseX 11.1, I get >> [XQDY0054] Static variable depends on itself: $local:lookup >> >> When I run it with Saxon-HE 12, I don't get this error. >> >> Is there anything I can do in my code to avoid this error? >> >> Thanks, >> Amanda >> > >

On Wed, Aug 14, 2024 at 3:43 PM Christian Grün <christian.gruen at gmail.com> wrote: > …thanks. I already guessed it wasn’t that easy ;) I’ve added it to [1]. > > In general, I hope we could get completely rid of self-dependency checks. > It was only defined for variables, not for functions, and I cannot see why > we still need it today. We are currently discussing this topic for version > 4.0 [2]. > > Best, > Christian > > [1] https://github.com/BaseXdb/basex/issues/2324 > [2] https://github.com/qt4cg/qtspecs/issues/1379 > > > > On Wed, Aug 14, 2024 at 1:02 PM Amanda Galtman <galtmana at proton.me> wrote: > >> Christian, thanks very much. >> >> I returned to my actual code, and it works with the latest snapshot dated >> today. >> >> By the way, I also retried the variations I had created when trying to >> explore workarounds, and one of them still doesn't work with the latest >> snapshot. It's not blocking me, but in case it is helpful, I reduced it to >> another small query that reproduces the error with today's snapshot. I know >> you said you fixed part of the problem, so you might not be surprised that >> the following code still triggers the error. >> >> xquery version "3.1"; >> >> declare variable $variant := >> if (exists(function-lookup(QName('nonexistent','nonexistent'), 0))) >> then >> ( (: not relevant :) ) >> else >> function-lookup(QName(' >> http://www.w3.org/2005/xpath-functions','string'), 1); >> >> declare variable $variant-fcns := $variant; >> >> declare function local:fcn() { >> $variant-fcns('abc') >> }; >> >> local:fcn() >> >> >> The levels of indirection (variable, variable, function, function call) >> seem to be relevant for the problem. If I make the code more direct, it >> works. >> >> Regards, >> Amanda >> >> On Monday, August 12th, 2024 at 5:16 AM, Christian Grün < >> christian.gruen at gmail.com> wrote: >> >> I managed to fix a part of the dependency problem. Your query should now >> be executable with the latest snapshot [1]. >> – Christian >> >> [1] https://files.basex.org/releases/latest/ >> >> >> >> On Fri, Aug 9, 2024 at 5:51 PM Amanda Galtman <galtmana at proton.me> wrote: >> >>> Hi, all. >>> >>> I'm seeing an error in BaseX when I use function-lookup in both a global >>> variable and a function, where the function relies on the variable. I >>> reduced the situation to the following small query: >>> >>> xquery version "3.1"; >>> declare variable $local:lookup := function-lookup(QName("nonexistent", >>> "nonexistent"), 1); >>> declare function local:myfcn() { >>> let $f := ($local:lookup, function-lookup(QName(' >>> http://www.w3.org/2005/xpath-functions','string'), 1))[1] >>> return $f('a') >>> }; >>> local:myfcn() >>> >>> When I run it with BaseX 11.1, I get >>> [XQDY0054] Static variable depends on itself: $local:lookup >>> >>> When I run it with Saxon-HE 12, I don't get this error. >>> >>> Is there anything I can do in my code to avoid this error? >>> >>> Thanks, >>> Amanda >>> >> >>

On Wednesday, September 18th, 2024 at 7:08 AM, Christian Grün <christian.gruen at gmail.com> wrote: > Hi Amanda, > > The last query you reported back to us is now evaluated successfully [1]. > > In addition, XQuery 4 will allow all of us to write self-referencing variable declarations (it’s already supported by the latest snapshot): > > declare variable $factorial := fn($x) { > if($x > 1) then $x + $factorial($x - 1) else $x > }; > $factorial(5) > > All the best, > Christian > > [1] https://github.com/BaseXdb/basex/issues/2324#issuecomment-2288790599 > > On Wed, Aug 14, 2024 at 3:43 PM Christian Grün <christian.gruen at gmail.com> wrote: > >> …thanks. I already guessed it wasn’t that easy ;) I’ve added it to [1]. >> >> In general, I hope we could get completely rid of self-dependency checks. It was only defined for variables, not for functions, and I cannot see why we still need it today. We are currently discussing this topic for version 4.0 [2]. >> >> Best, >> Christian >> >> [1] https://github.com/BaseXdb/basex/issues/2324 >> [2] https://github.com/qt4cg/qtspecs/issues/1379 >> >> On Wed, Aug 14, 2024 at 1:02 PM Amanda Galtman <galtmana at proton.me> wrote: >> >>> Christian, thanks very much. >>> >>> I returned to my actual code, and it works with the latest snapshot dated today. >>> >>> By the way, I also retried the variations I had created when trying to explore workarounds, and one of them still doesn't work with the latest snapshot. It's not blocking me, but in case it is helpful, I reduced it to another small query that reproduces the error with today's snapshot. I know you said you fixed part of the problem, so you might not be surprised that the following code still triggers the error. >>> >>> xquery version "3.1"; >>> >>> declare variable $variant := >>> if (exists(function-lookup(QName('nonexistent','nonexistent'), 0))) >>> then >>> ( (: not relevant :) ) >>> else >>> function-lookup(QName('http://www.w3.org/2005/xpath-functions','string'), 1); >>> >>> declare variable $variant-fcns := $variant; >>> >>> declare function local:fcn() { >>> $variant-fcns('abc') >>> }; >>> >>> local:fcn() >>> >>> The levels of indirection (variable, variable, function, function call) seem to be relevant for the problem. If I make the code more direct, it works. >>> >>> Regards, >>> Amanda >>> >>> On Monday, August 12th, 2024 at 5:16 AM, Christian Grün <christian.gruen at gmail.com> wrote: >>> >>>> I managed to fix a part of the dependency problem. Your query should now be executable with the latest snapshot [1]. >>>> – Christian >>>> >>>> [1] https://files.basex.org/releases/latest/ >>>> >>>> On Fri, Aug 9, 2024 at 5:51 PM Amanda Galtman <galtmana at proton.me> wrote: >>>> >>>>> Hi, all. >>>>> >>>>> I'm seeing an error in BaseX when I use function-lookup in both a global variable and a function, where the function relies on the variable. I reduced the situation to the following small query: >>>>> >>>>> xquery version "3.1"; >>>>> declare variable $local:lookup := function-lookup(QName("nonexistent", "nonexistent"), 1); >>>>> declare function local:myfcn() { >>>>> let $f := ($local:lookup, function-lookup(QName('http://www.w3.org/2005/xpath-functions','string'), 1))[1] >>>>> return $f('a') >>>>> }; >>>>> local:myfcn() >>>>> >>>>> When I run it with BaseX 11.1, I get >>>>> [XQDY0054] Static variable depends on itself: $local:lookup >>>>> >>>>> When I run it with Saxon-HE 12, I don't get this error. >>>>> >>>>> Is there anything I can do in my code to avoid this error? >>>>> >>>>> Thanks, >>>>> Amanda

Hmm, what if there's a $factorial in scope already? (this is a > technique i teach for taking advantage of closures to hide data)

> > > If I use $x * $factorial($x - 1) >

>

On Wed, 2024-09-18 at 13:08 +0200, Christian Grün wrote: > > In addition, XQuery 4 will allow all of us to write self-referencing > variable declarations (it’s already supported by the latest > snapshot): > > declare variable $factorial := fn($x) { > if($x > 1) then $x + $factorial($x - 1) else $x > }; > $factorial(5)

> >

On Wed, Sep 18, 2024 at 01:08:17PM +0200, Christian Grün scripsit: > In addition, XQuery 4 will allow all of us to write self-referencing > variable declarations (it’s already supported by the latest snapshot): > > declare variable $factorial := fn($x) { > if($x > 1) then $x + $factorial($x - 1) else $x > }; > $factorial(5)

On Thu, 2024-09-19 at 09:01 -0400, Liam R. E. Quin wrote: > \ > Hmm, what if there's a $factorial in scope already? (this is a > technique i teach for taking advantage of closures to hide data)

>

On Thu, Sep 19, 2024 at 04:08:34PM +0200, Christian Grün scripsit:

> Integers in BaseX are limited to 64bit (that’s something the spec allows). > You can use decimals to work with greater numbers: > > declare variable $factorial := fn($x) { > if($x > 1) then $x * $factorial($x - 1) else $x > }; > $factorial(1000.0) > > If you need even larger results, you can use a tail-call-optimized variant… > > declare variable $factorial := fn($x, $result) { > if($x > 1) then $factorial($x - 1, $x * $result) else $result > }; > $factorial(100000.0, 1) > > …or fold-left: > > fold-left(1 to 100000, 1.0, op('*')) > > Hope this helps,